scholarly journals Numerical Flow Modeling of Artificial Ocean Upwelling

2022 ◽  
Vol 8 ◽  
Author(s):  
Jost Kemper ◽  
Ulf Riebesell ◽  
Kai Graf
Keyword(s):  
Surface Layer ◽  
Fluid Dynamic ◽  
Lower Boundary ◽  
Deep Ocean ◽  
Passive Scalar ◽  
Source Modeling ◽  
Deep Ocean Water ◽  
Flow Phenomena ◽  
Numerical Flow Modeling ◽  
Mixed Surface Layer

Artificial Upwelling (AU) of nutrient-rich Deep Ocean Water (DOW) to the ocean's sunlit surface layer has recently been put forward as a means of increasing marine CO2 sequestration and fish production. AU and its possible benefits have been studied in the context of climate change mitigation as well as food security for a growing human population. However, extensive research still needs to be done into the feasibility, effectiveness and potential risks, and side effects associated with AU to be able to better predict its potential. Fluid dynamic modeling of the AU process and the corresponding inorganic nutrient transport can provide necessary information for a better quantification of the environmental impacts of specific AU devices and represents a valuable tool for their optimization. Yet, appropriate capture of all flow phenomena relevant to the AU process remains a challenging task that only few models are able to accomplish. In this paper, simulation results obtained with a newly developed numerical solution method are presented. The method is based on the open-source modeling environment OpenFOAM. It solves the unsteady Reynolds-Averaged Navier-Stokes (RANS) equations with additional transport equations for energy, salinity, and inorganic nutrients. The method aims to be widely applicable to oceanic flow problems including temperature- and salinity-induced density stratification and passive scalar transport. The studies presented in this paper concentrate on the direct effects of the AU process on nutrient spread and concentration in the ocean's mixed surface layer. Expected flow phenomena are found to be captured well by the new method. While it is a known problem that cold DOW that is upwelled to the surface tends to sink down again due to its high density, the simulations presented in this paper show that the upwelled DOW settles at the lower boundary of the oceans mixed surface layer, thus keeping a considerable portion of the upwelled nutrients available for primary production. Comparative studies of several design variants, with the aim of maximizing the amount of nutrients that is retained inside the mixed surface layer, are also presented and analyzed.

Computational Fluid Dynamic Applications for Jet Propulsion System Integration

1991 ◽  
Vol 113 (1) ◽  
pp. 40-50 ◽  
Author(s):  
R. H. Tindell
Keyword(s):  
System Integration ◽  
Fluid Dynamic ◽  
Low Cost ◽  
Separated Flow ◽  
Propulsion System ◽  
Navier Stokes ◽  
Aerospace Vehicles ◽  
Design Engineers ◽  
Flow Phenomena ◽  
The Impact

The impact of computational fluid dynamics (CFD) methods on the development of advanced aerospace vehicles is growing stronger year by year. Design engineers are now becoming familiar with CFD tools and are developing productive methods and techniques for their applications. This paper presents and discusses applications of CFD methods used at Grumman to design and predict the performance of propulsion system elements such as inlets and nozzles. The paper demonstrates techniques for applying various CFD codes and shows several interesting and unique results. A novel application of a supersonic Euler analysis of an inlet approach flow field, to clarify a wind tunnel-to-flight data conflict, is presented. In another example, calculations and measurements of low-speed inlet performance at angle of attack are compared. This is highlighted by employing a simplistic and low-cost computational model. More complex inlet flow phenomena at high angles of attack, calculated using an approach that combines a panel method with a Navier-Stokes (N-S) code, is also reviewed. The inlet fluid mechanics picture is rounded out by describing an N-S calculation and a comparison with test data of an offset diffuser having massively separated flow on one wall. Finally, the propulsion integration picture is completed by a discussion of the results of nozzle-afterbody calculations, using both a complete aircraft simulation in a N-S code, and a more economical calculation using an equivalent body of revolution technique.

scholarly journals Temperature statistics above a deep-ocean sloping boundary

2015 ◽  
Vol 775 ◽  
pp. 415-435 ◽  
Author(s):  
Andrea A. Cimatoribus ◽  
H. van Haren
Keyword(s):  
Deep Ocean ◽  
Passive Scalar ◽  
Convective Activity ◽  
Flow State ◽  
Ocean Turbulence ◽  
The North ◽  
Numerical Studies ◽  
Eastern Atlantic Ocean ◽  
North Eastern ◽  
Turbulence Scaling

We present a detailed analysis of temperature statistics in an oceanographic observational dataset. The data are collected using a moored array of thermistors,$100~\text{m}$tall and starting$5~\text{m}$above the bottom, deployed during four months above the slopes of a Seamount in the north-eastern Atlantic Ocean. Turbulence at this location is strongly affected by the semidiurnal tidal wave. Mean stratification is stable in the entire dataset. We compute structure functions, of order up to 10, of the distributions of temperature increments. Strong intermittency is observed, in particular, during the downslope phase of the tide, and farther from the solid bottom. In the lower half of the mooring during the upslope phase, the temperature statistics are consistent with those of a passive scalar. In the upper half of the mooring, the temperature statistics deviate from those of a passive scalar, and evidence of turbulent convective activity is found. The downslope phase is generally thought to be more shear-dominated, but our results suggest on the other hand that convective activity is present. High-order moments also show that the turbulence scaling behaviour breaks at a well-defined scale (of the order of the buoyancy length scale), which is however dependent on the flow state (tidal phase, height above the bottom). At larger scales, wave motions are dominant. We suggest that our results could provide an important reference for laboratory and numerical studies of mixing in geophysical flows.

scholarly journals Metals of Deep Ocean Water Increase the Anti-Adipogenesis Effect of Monascus-Fermented Product via Modulating the Monascin and Ankaflavin Production

Marine Drugs ◽  
2016 ◽  
Vol 14 (6) ◽  
pp. 106 ◽  
Author(s):  
Tzu-Ying Lung ◽  
Li-Ya Liao ◽  
Jyh-Jye Wang ◽  
Bai-Luh Wei ◽  
Ping-Yi Huang ◽  
...  
Keyword(s):  
Deep Ocean ◽  
Ocean Water ◽  
Deep Ocean Water ◽  
Fermented Product

scholarly journals Characteristics of Tofu Coagulants Extracted from Sea Tangle Using Treated Deep Ocean Water

2007 ◽  
Vol 40 (3) ◽  
pp. 113-116 ◽  
Author(s):  
Seung-Won Lee ◽  
Hyeon-Joo Kim ◽  
Deok-Soo Moon ◽  
Ah-Ree Kim ◽  
In-Hak Jeong
Keyword(s):  
Deep Ocean ◽  
Ocean Water ◽  
Deep Ocean Water

Collecting amino acids in the Enceladus plume

2018 ◽  
Vol 18 (1) ◽  
pp. 47-59 ◽  
Author(s):  
Melissa Guzman ◽  
Ralph Lorenz ◽  
Dana Hurley ◽  
William Farrell ◽  
John Spencer ◽  
...  
Keyword(s):  
Amino Acids ◽  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Free Amino Acids ◽  
Free Amino ◽  
Deep Ocean ◽  
Mass Rate ◽  
Bubble Bursting ◽  
Deep Ocean Water

AbstractWe numerically model the dynamics of the Enceladus plume ice grains and define our nominal plume model as having a particle size distributionn(R) ~R−qwithq= 4 and a total particulate mass rate of 16 kg s−1. This mass rate is based on average plume brightness observed by Cassini across a range of orbital positions. The model predicts sample volumes of ~1600 µg for a 1 m2collector on a spacecraft making flybys at 20–60 km altitudes above the Enceladus surface. We develop two scenarios to predict the concentration of amino acids in the plume based on these assumed sample volumes. We specifically consider Glycine, Serine, α-Alanine, α-Aminoisobutyric acid and Isovaline. The first ‘abiotic’ model assumes that Enceladus has the composition of a comet and finds abundances between 2 × 10−6to 0.003 µg for dissolved free amino acids and 2 × 10−5to 0.3 µg for particulate amino acids. The second ‘biotic’ model assumes that the water of Enceladus's ocean has the same amino acid composition as the deep ocean water on Earth. We compute the expected captured mass of amino acids such as Glycine, Serine, and α-Alanine in the ‘biotic’ model to be between 1 × 10−5to 2 × 10−5µg for dissolved free amino acids and dissolved combined amino acids and about 0.0002 µg for particulate amino acids. Both models consider enhancements due to bubble bursting. Expected captured mass of amino acids is calculated for a 1 m2collector on a spacecraft making flybys with a closest approach of 20 km during mean plume activity for the given nominal particle size distribution.

Ocean-Bottom Strong-Motion Observations in the Nankai Trough by the DONET Real-Time Monitoring System

2018 ◽  
Vol 52 (3) ◽  
pp. 100-108 ◽  
Author(s):  
Takeshi Nakamura ◽  
Narumi Takahashi ◽  
Kensuke Suzuki
Keyword(s):  
Real Time ◽  
Nankai Trough ◽  
Strong Motion ◽  
Deep Ocean ◽  
Disaster Mitigation ◽  
Ocean Bottom ◽  
Source Modeling ◽  
Origin Time ◽  
Subduction Earthquakes ◽  
Sediment Layers

AbstractThe deployment of real-time permanent ocean-bottom seismic and tsunami observatories is significant for disaster mitigation and prevention during the occurrence of large subduction earthquakes near trough areas. On April 1, 2016, a moderate-sized suboceanic earthquake occurred beneath Dense Oceanfloor Network System for Earthquakes and Tsunamis (DONET) stations that were recently deployed in deep ocean-bottom areas near the Nankai Trough in southwest Japan. P-waves arrived at the ocean-bottom station within 4 s of the origin time, which was 6 and 13 s earlier than the arrival of P- and S-waves at a land station in the coastal area, respectively; this implies earlier detection of strong motion than at land stations. However, the waveforms are amplified by sediment layers and even contaminated with acceleration offsets at some stations, which would lead to overestimations during source investigations. Such amplification and offset did not occur at a borehole station connected to DONET. The amplifications caused by the sediment layers and the offset were found to have a considerable spatial variation, not only between the DONET stations and land and borehole stations but also among the DONET stations, implying that the amplitude evaluation could be unstable. Therefore, procedures for correcting or suppressing the amplification and offset problem are required for conducting waveform analyses, such as magnitude estimations and source modeling, during large subduction earthquakes.

About tsunamis

2004 ◽  
Vol 89 (516) ◽  
pp. 437-440 ◽  
Author(s):  
Maurice N. Brearley
Keyword(s):  
Small Amplitude ◽  
Tsunami Wave ◽  
Deep Ocean ◽  
Ocean Floor ◽  
Ocean Water ◽  
Long Distance ◽  
Shore Line ◽  
Deep Ocean Water

A tsunami usually starts on deep ocean water as a result of a submarine earthquake. A tsunami wave is very long, even as much as tens of kilometres, but of only very small amplitude, typically less than half a metre (Bascom [1]). In mid-ocean, the passage of a tsunami is imperceptible, but on reaching a shore it can achieve great heights and can deliver massive surges of water. Before the arrival of the first surge, and between subsequent surges, the water at a shore line usually retracts for a long distance, leaving bare large areas of ocean floor that are normally under water. This paper analyses the behaviour of a tsunami, and explains how its mid-ocean character is transformed to produce such massive surges of water at a shore line.

Supplementation of nanofiltrated deep ocean water ameliorate the progression of osteoporosis in ovariectomized rat via regulating osteoblast differentiation

2020 ◽  
Vol 44 (7) ◽  
Author(s):  
Pei‐Chen Chen ◽  
Yi‐Chen Lee ◽  
Hsing‐Yu Jao ◽  
Chi‐Ping Wang ◽  
Anthony Jacobs ◽  
...  
Keyword(s):  
Osteoblast Differentiation ◽  
Deep Ocean ◽  
Ovariectomized Rat ◽  
Ocean Water ◽  
Deep Ocean Water

scholarly journals Neoproterozoic Nafun Group Sediments from Oman Affected by an Active Continental Margin

Minerals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 511
Author(s):  
Liang Yue ◽  
Veerle Vandeginste
Keyword(s):  
Continental Margin ◽  
Water Oxidation ◽  
Tectonic Setting ◽  
Active Continental Margin ◽  
Trace Element Analysis ◽  
Deep Ocean ◽  
Geochemical Data ◽  
Ocean Water ◽  
Element Analysis ◽  
Deep Ocean Water

The Neoproterozoic era is a time of major environmental change in Earth history. The Ediacaran period (635–541 Ma), the uppermost division of Precambrian time, is characterized by the remarkable Shuram excursion (largest C isotope negative excursion), a deep ocean water oxidation event, and Ediacaran biota. The Nafun Group of Oman provides a well-preserved and mostly continuous section of an Ediacaran succession. Based on geochemical data from the Nafun Group, the Shuram excursion (SE) and deep ocean oxidation hypotheses were proposed. Now, we sampled this section at high stratigraphic resolution, and present here the petrographical and geochemical analysis of the Khufai, Shuram and Buah Formations. The major and trace element analysis of shales from the Shuram Formation indicates that northern Oman was an active continental margin environment in Neoproterozoic times. The provenance of the Shuram Formation was primarily mafic and intermediate igneous rocks. With the unsteady tectonic setting, the development of the Nafun Group was influenced by hydrothermal supply and volcaniclastic input. Based on the V/Cr and U/Th ratio of the samples from the Nafun Group, our study reveals the transition of the ocean water redox environment, which is connected to the rise and fall of the Ediacaran biota. Our study constrains the tectonic setting of northern Oman and the petrography and geochemical data from the Nafun Group for the hydrothermal and volcaniclastic supply. Thus, our study acknowledges more factors for the explanation of the Ediacaran conundrums.

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